Department of Orthopaedic Surgery, General Hospital of Chinese People's Liberation Army, 28 Fu-Xing Road, 100853, Beijing, People's Republic of China.
Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, People's Republic of China.
J Orthop Surg Res. 2021 Jul 3;16(1):428. doi: 10.1186/s13018-021-02581-5.
To compare the biomechanical stability of transsacral-transiliac screw fixation and lumbopelvic fixation for "H"- and "U"-type sacrum fractures with traumatic spondylopelvic dissociation.
Finite element models of "H"- and "U"-type sacrum fractures with traumatic spondylopelvic dissociation were created in this study. The models mimicked the standing position of a human. Fixation with transsacral-transiliac screw fixation, lumbopelvic fixation, and bilateral triangular fixation were simulated. Biomechanical tests of instability were performed, and the fracture gap displacement, anteflexion, rotation, and stress distribution after fixation were assessed.
For H-type fractures, the three kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac screw fixation in the vertical and anteflexion directions, bilateral triangular fixation > transsacral-transiliac S1 and S2 screw fixation > lumbopelvic fixation in rotation. The largest displacements in the vertical, anteflexion, and rotational directions were 0.57234 mm, 0.37923 mm, and 0.13076 mm, respectively. For U-type fractures, these kinds of fixation ranked by stability were bilateral triangular fixation > lumbopelvic fixation > transsacral-transiliac S1 and S2 screw fixation > transsacral-transiliac S1 screw fixation in the vertical, anteflexion, and rotational directions. The largest displacements in the vertical, anteflexion, and rotational directions were 0.38296 mm, 0.33976 mm, and 0.05064 mm, respectively.
All these kinds of fixation met the mechanical criteria for clinical applications. The biomechanical analysis showed better bilateral balance with transsacral-transiliac screw fixation. The maximal displacement for these types of fixation was less than 1 mm. Percutaneous transsacral-transiliac screw fixation can be considered the best option among these kinds of fracture fixation.
比较经骶骨-髂骨螺钉固定与腰骶骨盆固定治疗创伤性骨盆脊柱分离的“H”型和“U”型骶骨骨折的生物力学稳定性。
本研究建立了创伤性骨盆脊柱分离的“H”型和“U”型骶骨骨折的有限元模型。模型模拟人体站立位。模拟经骶骨-髂骨螺钉固定、腰骶骨盆固定和双侧三角固定。进行不稳定的生物力学试验，评估固定后的骨折间隙位移、前屈、旋转和应力分布。
对于 H 型骨折，在垂直和前屈方向上，三种固定方式的稳定性依次为双侧三角固定>腰骶骨盆固定>经骶骨-髂骨螺钉固定，在旋转方向上，双侧三角固定>经骶骨-髂骨 S1 和 S2 螺钉固定>腰骶骨盆固定。在垂直、前屈和旋转方向上的最大位移分别为 0.57234mm、0.37923mm 和 0.13076mm。对于 U 型骨折，在垂直、前屈和旋转方向上，这三种固定方式的稳定性依次为双侧三角固定>腰骶骨盆固定>经骶骨-髂骨 S1 和 S2 螺钉固定>经骶骨-髂骨 S1 螺钉固定。在垂直、前屈和旋转方向上的最大位移分别为 0.38296mm、0.33976mm 和 0.05064mm。
所有这些固定方式均符合临床应用的力学标准。生物力学分析显示经骶骨-髂骨螺钉固定具有更好的双侧平衡。这些固定方式的最大位移小于 1mm。经皮经骶骨-髂骨螺钉固定可被认为是这些骨折固定方式中最佳的选择。
